The time-multiplexed technique for viewing electronic stereoscopic images is now a standard viewing modality for computer graphics and video. During the past decade, electro-stereoscopic displays have become a well-established means for viewing images on workstations in applications such as molecular modeling and various types of scientific visualiztion. In addition, video systems for various applications such as medical imaging have had some success in the marketplace. Lately, the application of time-multiplexed displays for the mass consumer personal computer market has been attempted with mixed success.
All of these systems use liquid crystal (xe2x80x9cLCxe2x80x9d) shuttering eyewear for viewing stereoscopic images, such as CrystalEyes(copyright) eyewear or SimulEyes(copyright) eyewear, both manufactured by StereoGraphics Corporation of San Rafael, Calif. Various aspects of these products are described in the following patents: U.S. Pat. No. 4,884,876 entitled xe2x80x9cAchromatic Liquid Crystal Shutter For Stereoscopic And Other Applications;xe2x80x9d U.S. Pat. No. 4,967,268 entitled xe2x80x9cLiquid Crystal Shutter System For Stereoscopic And Other Applications;xe2x80x9d U.S. Pat. No. 5,117,302 entitled xe2x80x9cHigh Dynamic Range Electro-Optical Shutter For Stereoscopic And Other Applications;xe2x80x9d U.S. Pat. No. 5,181,133 entitled xe2x80x9cDrive Method For Twisted Nematic Liquid Crystal Shutters For Stereoscopic And Other Applications; U.S. Pat. No. 5,463,428 entitled xe2x80x9cWireless Active Eyewear For Stereoscopic Applications;xe2x80x9d and U.S. Pat. No. 5,572,250 entitled xe2x80x9cUniversal Electronic Stereoscopic Display.xe2x80x9d
LC shuttering eyewear for the mass consumer market must be manufactured at the lowest possible cost of goods in order to compete in what is essentially a commodity marketplace. Therefore, it is vitally important for the manufacturer of such eyewear to obtain every cost cutting competitive advantage in order to prevail in the marketplace. Such means are the subject of this disclosure.
The present invention is an apparatus and corresponding method for reducing the cost of manufacture of stereoscopic eyewear. The apparatus includes several features which lower the manufacturing cost by reducing the labor content and by providing an appropriate housing for the electronic components. One feature reduces assembly time by eliminating a complex wiring harness and the need to make individual connections. Another feature includes the driver electronics within the wired eyewear itself rather than within a cable or an adapter.
The apparatus includes a pair of liquid crystal shutters each having a contact pad for receiving electrical drive signals and a frame having a pair of eye openings therein suitable for receiving the shutters. An electrical cable is incorporated with the frame. The cable has a plurality of wires for providing drive signals to the shutters. Each wire has its end terminated with a fixed electrical contact. The frame includes an electrical contact area which includes a portion adapted to securely receive the electrical wire contacts. A conductive circuit trace is formed on an insulating material; which may be the frame or the lens assembly, or a separately added mask. The lens assembly attached to the frame to rigidly hold the frame, the shutters and the conductive trace in intimate juxtaposition.
In a preferred embodiment, conductive elastomers are used to provide electrical contact between portions of the conductive trace and the shutter contact pads and/or the electrical contact area of the frame.
In another embodiment, a printed circuit board is incorporated at the contact area of the frame. The printed circuit board is adapted to condition the drive signals to appropriately drive the liquid crystal shutters, thereby eliminating the need for a separate driver circuit external to the eyewear.
Many useful variations will be obvious to one with skill in this technology upon considering the following detailed description and drawings.